The 3M™ Multi-Touch Display M2767PW incorporates 3M Projected Capacitive Technology and offers full multi-touch capabilities with less than 10 millisecond response. This means fast, accurate touch response over the entire touch surface.
0 to +40 degrees C (anticipated)
, Non-condensing 90% (anticipated)
, Relative Humidity
Operating System Support
, Windows 7/Vista/XP
0.248 mm x 0.248 mm
External 110/220 VAC Power Supply
-10 to +60 degrees C (anticipated)
Touch Point Speed
3M Projected Capacitive
100 mm x 100 mm
Video Response Time
25 milliseconds (typical)
Horizontal/Vertical: 178 degrees typical
How Projected Capacitive Technology Works
Projected capacitive technologies detect touch by measuring the capacitance at each addressable electrode. When a finger or a conductive stylus approaches an electrode, it disturbs the electromagnetic field and alters the capacitance. This change in capacitance can be measured by the electronics and then converted into X,Y locations that the system can use to detect touch.
3M Project Capacitive Technology (3M PCT) is based on mutual capacitance to create multi-touch interactive. Mutual capacitance is the intentional or unintentional capacitance between two "charge holding objects” (see illustration). Projected capacitance touchscreens intentionally create mutual capacitance between elements of columns and rows in the vicinity where each intersect the other. This allows the system electronics to measure each node (intersection) individually to detect multiple touches on the screen during one screen scan.
When a finger touches near an intersection, some of the mutual capacitance between the row and column is coupled to the finger which reduce the capacitance at the intersection as measured by the system electronics. This reduced capacitance crosses the "touch threshold" set by the electronics indicating a touch has occurred.